DE102008030244A1 - Method for supporting percutaneous interventions - Google Patents

Abstract

The present invention relates to a method for assisting percutaneous interventions in which, prior to intervention with a C-arm X-ray system or a robot-based X-ray system, 2-D X-ray recordings are recorded at different projection angles from an object area and from the 2-D X-ray recordings 3-D image data of the object area are reconstructed. Before and / or during the intervention, one or more 2-D or 3-D ultrasound images are recorded with an external ultrasound system and registered with the 3-D image data. the 2-D or 3-D ultrasound images are then superimposed with the 3-D image data set or a target region segmented therefrom or displayed side by side in the same perspective. The method allows a low-radiation monitoring of a puncture or a biopsy.

Description

The The present invention relates to a method of assistance of percutaneous interventions at which before the intervention 3-D image data set of an object area comprising the target area created and monitored the intervention through a real-time imaging becomes.

percutaneous Procedures such as biopsies or punctures play in diagnostics and therapy of different diseases play an important role. The principle of percutaneous intervention is based on the puncture a pathological process, for example a tumor in the liver, through the skin. Thus, for example, with special biopsy needles tissue samples for diagnostic purposes. Allow percutaneous interventions also the implementation of a therapy, such as the TIPSS procedure (TIPSS: transcutaneous intrahepatic postage-systemic shunt), the drainage an abscess or the thermoablation of a solitary Liver metastasis. A percutaneous puncture is usually followed a previous diagnostic imaging by computer tomography (CT), magnetic resonance imaging (MRI) or ultrasound and will monitored during the procedure by a real time imaging and controlled.

by virtue of minimal invasiveness, secure access routes and The local therapy option will be percutaneous interventions continue to increase over the next few years. By the improved Diagnostics can detect potential pathologies in ever-earlier ones Stages discovered and ever smaller herd in difficult to access Positions are dotted. Nevertheless, the percutaneous diagnosis possesses and therapy also some limitations. So will in the Literature indicated a complication rate between 3.9% and 23.9%. These are mostly non-life threatening Bleeding, hematomas, pneumothoraces or organ injuries. Yet there is also a risk of dying from such an operation, especially if accidentally injured a large vessel has been. Another serious problem is a malfunction The rate of erroneous or incomplete punctures is reported in the literature as up to 30%. Malpositions can lead to a false negative diagnosis or not cause sufficient therapy dose in the desired target area. The number of faulty punctures must therefore be both in the interests of Patients as well as from the point of view of efficient and cost-saving medicine are kept as low as possible.

The Difficulty of an exact puncture lies in the variability the target region by respiratory movements, by the needle feed shifts caused Deformation of organ and hearth as well as in possible unpredictable movements of the patient.

That's how it describes DE 10 2005 032 755 A1 a system for performing and monitoring minimally invasive procedures, in which a C-arm X-ray system records 2-D X-ray images of an object area at different projection angles and reconstructs 3D image data from the 2D object area. With the same X-ray system, 2-D X-ray images can then be recorded in real time during the intervention and superimposed on the representation of the 3-D image data. Furthermore, in this system with an ultrasonic catheter 3-D ultrasound images can be performed in real time and registered with the high-resolution 3-D image data of the C-arm X-ray device and displayed.

at However, the latter method requires either deposition ionizing radiation during the procedure for the patient can be accepted or the application is in the Case of the ultrasound catheter limited to certain areas. In particular, can be with a Ultraschallka theter usually Do not perform biopsies or punctures.

The The object of the present invention is a method to provide support for percutaneous interventions, dedicated to the monitoring of biopsies and Punktionen is suitable and the radiation exposure during the Reduced surgery for the patient.

The Task is with the method according to claim 1 solved. Advantageous embodiments of the method are Subject of the dependent claims or can be the following description and the embodiment remove.

In the proposed method of assisting percutaneous interventions, prior to intervention with a C-arm X-ray system or a robot-based X-ray system, 2-D X-ray images are recorded at different projection angles with a first trigger from an object area and from the 2-D X-ray scans 3-D X-ray image data of the object area reconstructed. The C-arm X-ray system may be, for example, act. To the system DynaCT ^® from Siemens. In the reconstructed 3-D image data, the target area of the intervention is segmented. Before and / or during the intervention, one or more 2-D or 3-D ultrasound images are then recorded with an external ultrasound system, the at least one part of said object area, and registered with the 3-D X-ray image data. The 2-D or 3-D ultrasound images are recorded at a lower resolution than the 3-D X-ray image data with the X-ray system. The 2-D or 3-D ultrasound images are then superimposed during the intervention with the 3-D X-ray image data and / or the target area segmented therefrom or displayed separately in the same perspective.

at the proposed method thus becomes ultrasound imaging with an external ultrasound machine with 3-D X-ray imaging with a C-arm X-ray system or a robot-based X-ray system combined. Under an external ultrasound system Here is an ultrasound system to understand that outside of the body is arranged and therefore not introduced into the body becomes. A robot-based X-ray system has a one or more robotic arms guided imaging system on. With the robot-based X-ray system can be in the same way as with an X-ray C-arm system 2-D X-ray images record the object area at different projection angles, from which then a 3-D X-ray image data set reconstructed can be. The ultrasound imaging during the intervention offers the advantage of imaging in real time without radiation exposure for the patient. A high resolution will open the other side with the pre-intervention X-ray imaging reached. The combination of the C-arm or robot-based X-ray system with The external ultrasound imaging has the advantage of having the registry in many cases can be done in a simpler way than When using a CT system, this usually involves a rearrangement of the patient between different rooms for the CT scan and the implementation of the intervention requires. The C-arm X-ray system or the robot-based X-ray system offer against it a very good accessibility to the patient and can therefore be used in the same room in which the intervention takes place. A spatial registration of ultrasound system and X-ray system is thereby significantly simplified.

For Ultrasound imaging offers different variants, however, the examples below are not exhaustive Represent enumeration. Thus, in one embodiment a Ultrasonic head can be used, which generates two-dimensional images. By controlled movement of the ultrasound head for the recording of different 2-D images can be a record be obtained from the succession of the recorded by Hin 2-D images taking into account their known recording position a 3-D image can be generated. The third dimension is over the Knowledge of the movement data of the ultrasound head during get the record of each picture.

In In another embodiment, an ultrasound head can be used which produces two-dimensional images and moves by machine can be. Through the machine movement can be a three-dimensional Volume can be sampled evenly. The three-dimensional Image data set is created in the same way as in the previous embodiment.

Farther may according to another embodiment, an ultrasonic head be used, which produces two-dimensional images and with a Position sensor is equipped. This ultrasonic head can both be moved manually as well as mechanically, with the spatial Assignment of images for creating a 3-D image via the recorded positions can be done in real time.

In In another embodiment, an ultrasonic head with a rotatable 2-D array inserted by a controlled rotation of the 2-D array can directly generate three-dimensional images. This Ultrasonic head can also be used with a position sensor be equipped.

Position detection systems, as used in connection with the ultrasound heads used can be, for. B. on magnetic or based on optical principles, as the expert from the state the technique is known.

at the proposed method is not always necessary to create a 3-D ultrasound image. Rather, one can each 2-D ultrasound image with a corresponding, from the 3-D X-ray image data set shown superimposed 2-D cross-sectional image become. Basically he follows an overlay the ultrasound images with the X-ray images preferably such that at least one of the images in transparency for the user is adjustable. In the overlay can the 2-D or 3-D ultrasound images with the 3-D X-ray image or a picture taken from it, or even just the segmented one Image of the target area are superimposed. The feed of the interventional instruments, in particular a puncture or Biopsy needle, it is monitored with the ultrasound images in real time. The target area, for example a tumor, can hereby be colored be highlighted.

Optionally, for example during a movement of the patient, a new recording of the image data and / or a new registration can take place. Thus, for example, a new 3-D image data record can be recorded with the X-ray system. This can be in lower or in high resolution. Additionally or alternatively, new 3-D ultrasound images or 2-D ultrasound images may also be recorded.

In In another possible embodiment, the patient or organ movements, for example of the lung or diaphragm, in the or position sensors attached to the patient. Based This motion information can then update the registry or a re-registration of the imaging systems. Furthermore, can also the originally created 3-D image data set or a part of it is suitably deformed to him by the Movement may have changed extent and location of the target area. In another variant can record new image data after detecting such movement then the originally created 3-D image data set or replace part of it.

By the proposed procedure will be a simpler and more accurate Registration of the imaging systems and thus a higher Puncture accuracy achieved. All modalities are in accessible to a room without having to umla the patient umla. The workflow is thereby simplified. Through the intervention-accompanying Ultrasound imaging will reduce the burden on the patient by ionizing Radiation minimized. Furthermore, the pre-intervention performed Creation of the 3-D X-ray image data set for the planning of the Intervention be used, so that on the previously usual Creation of a CT image dataset for the pre-interventional Planning can be dispensed with. By the fusion of X-ray image data and ultrasound image data complement the benefits of both imaging modalities.

The proposed method will be described below with reference to an embodiment in conjunction with the 1 again exemplified. The figure shows a schematic representation of the sequence in the implementation of the proposed method, wherein optional steps or paths are shown in dashed lines.

• Schritt 1: Aufnahme und Rekonstruktion eines 3-D-DynaCT-Datensatzes der Leber mit hoher Auflösung; Segmentierung des Zielgebietes, bspw. eines Tumors, und evtl. Farbdarstellung im Gesamt-DynaCT-Datensatz.
• Schritt 2: Aufnahme eines 3-D-Ultraschallbildes durch einen geeigneten Ultraschallkopf für 3-D-Bildgebung oder mehrerer 2-D-Ultraschallbilder bei bekannter räumlicher Lage des Ultraschallkopfes; ggf. Segmentierung des Zielgebietes in diesen Ultraschallbildern.
• Schritt 3: Registrierung der aufgezeichneten Ultraschallbilder (2-D- oder 3D) mit dem DynaCT-Datensatz.
• Schritt 4: Nadelvorschub unter Bildkontrolle, bis die Nadel die Zielregion in der Leber erreicht hat.

The workflow of the proposed method is described using a biopsy of the liver. The workflow includes the following steps:

• Step 1: Acquisition and reconstruction of a high-resolution 3-D DynaCT record of the liver; Segmentation of the target area, eg a tumor, and possibly color representation in the overall DynaCT dataset.
• Step 2: taking a 3-D ultrasound image through a suitable ultrasound head for 3-D imaging or multiple 2-D ultrasound images in a known spatial position of the ultrasound head; if necessary segmentation of the target area in these ultrasound images.
• Step 3: Register the recorded ultrasound images (2-D or 3D) with the DynaCT dataset.
• Step 4: Needle feed under image control until the needle reaches the target region in the liver.

The Color representation of the tumor in step 1, which can optionally be done serves to better detect the tumor for the user in the respective image representation. The segmentation can be manually or with known segmentation techniques semi-automatic or automatically. Following the recording and reconstruction of the 3-D X-ray image data set (DynaCT data set) Planning the biopsy done.

The Recording one or more 3-D ultrasound images or the individual 2-D ultrasound images can be taken with appropriate ultrasound systems, as already mentioned, for example, in the preceding description are.

For registration in step 3 different techniques can be used. Thus, the registration can be done, for example, on the basis of anatomical landmarks. These are selected by the physician in both image data sets to be registered, ie the ultrasound image and the x-ray image. This determines the transformation from one image to the other. Another possibility is to perform a greyscale intensity based 3D / 3-D image registration. For this purpose, different automatic methods are available, as they are, for example, in Joseph V. Hajnal et al., "Medical Image Registration", CRC, pp. 39-70, 2001 are described. The disclosure of this publication is incorporated in the present patent application with regard to the description of the registration methods. One of the 3-D images can also be replaced by a series of 2-D images when performing these procedures.

A Another possibility of registration is in one Surface adjustment of the two images to be registered After segmenting the ROI (ROI: Region of Interest), such as. of the tumor. The tumor serves as the central information for determination the transformation. Furthermore, a position sensor-based Registration possible in cases where one Ultrasonic head is used with a position sensor. The associated Localization system is firmly connected to the X-ray system, so that the position of the ultrasound head in the coordinate system the X-ray system is known at all times.

For image control of the needle feed in step 4, different visualization alternatives are available. So according to an alternative depending of the 2-D real-time ultrasound image are superimposed with a corresponding 2-D DynaCT cross-sectional image. This is particularly useful when using a localization system with the ultrasound head or in cases where the ultrasound head is not or only mechanically and controlled or traceable moved. If a two-dimensional ultrasound image intersects the DynaCT volume, this section also yields a two-dimensional DynaCT image, referred to above as the 2-D DynaCT cross-sectional image. The representation of the two images can be superimposed on one another or side by side on one or two image display devices, in particular a monitor. In this case, one of the images can be displayed semitransparent, wherein the strength of the transparency can be selected automatically either as a function of the gray value or determined by the user.

In another visualization alternative, the segmented tumor is superimposed in 3D in the fused DynaCT and real-time ultrasound images or in the fused real-time ultrasound images. This concerns the information of the segmented tumor tissue or other segmented structures. On the one hand, the ultrasound image can superimpose the segmented structures in three-dimensional space, allowing the visualization to be freely rotatable in space. On the other hand, the segmented structure can appropriately superimpose the plane of the 2-D ultrasound image. If the segmented structure does not intersect the ultrasound image, at least its projection and / or distance can be visualized. Such a visualization can, for example, the publication of Björn Meyer et al., "Layer-based illustration of medical volume data for intraoperative navigation", in: Proceedings: Image Processing for Medicine (BVM) 2006, pages 335-339, Springer 2006 , whose disclosure is included in the present patent application. This visualization serves to give the user depth information. This allows him to better estimate how deep the needle is in the tumor tissue.

In a further visualization alternative is the overlay the ultrasound images directly in the 3-D DynaCT dataset.

For Simultaneous visualization of 3-D and 2-D image data You can also use two separate screens.

While the implementation of the intervention, d. H. of the needle feed under image control, can also be a re-recording of image data and / or a new registration takes place. The needle feed leads under Circumstances to a deformation of the structures to be punctured in the organ. By re-recording a low-resolution DynaCT dataset can estimate the deformation field and this is the first high-resolution DynaCT record be applied to a more realistic imaging for to offer the further needle feed. The first high resolution DynaCT record is here with the information about modified the deformations.

In In another embodiment, a new DynaCT record in high resolution recorded. This further high resolved DynaCT record then replaces the previous one created a high-resolution DynaCT record completely. The current DynaCT dataset will be updated with the ultrasound images registered and merged. This also occurs in a case in no new DynaCT recording, just a new registration is carried out. When using an ultrasonic head, can be generated with the 3-D ultrasound imaging, a permanent Image-based registration of the current 3-D ultrasound images with the DynaCT record, since there is enough image information is present for a registration. Alternatively, the Movement of the patient or organ and / or the resulting deformation of the area of interest also by additional position sensors then be used as the basis for the re-registration be used.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 102005032755 A1 [0005]

Cited non-patent literature

• - Joseph V. Hajnal et al., "Medical Image Registration", CRC, pages 39 to 70, 2001. [0024]
• - Björn Meyer et al., "Layer-based illustration of medical volume data for intraoperative navigation", in: Proceedings: Image Processing for Medicine (BVM) 2006, pages 335-339, Springer 2006 [0027]

Claims (15)

Method for supporting percutaneous interventions, in which - before intervention with a C-arm X-ray system or a robot-based X-ray 2-D X-ray at different projection angles with a first resolution recorded from an object area and from the 2-D X-ray photographs 3-D image data of the object area are reconstructed, - one Target area of intervention in the reconstructed 3-D image data is segmented, - before and / or during the intervention with an external ultrasound system one or more 2-D or 3-D ultrasound images are recorded, at least include part of the object area, and the 3-D image data be registered with the 2-D or 3-D ultrasound images with a second resolution can be recorded, the lower as the first resolution can be, and - the 2-D or 3-D ultrasound images during the intervention with the 3-D image data and / or the segmented target area at one Image display device superimposed or side by side in same perspective. The method of claim 1, wherein each of a 2-D ultrasound image superimposed with a corresponding 2-D cross-sectional image from the 3-D image data is pictured. The method of claim 1, wherein the segmented Target area is faded into the 3-D ultrasound image. The method of claim 1, wherein in the overlay at least one of the images with adjustable transparency superimposed becomes. Method according to one of claims 1 to 4, in which an ultrasonic head is used, the 2-D ultrasound images generated and the 2-D ultrasound images according to their recording position be strung together to a 3-D ultrasound image data set to create. Method according to one of claims 1 to 4, in which an ultrasonic head with a rotatable 2-D ultrasonic transducer array is used by a controlled rotation of the array three-dimensional Can generate images directly. The method of claim 5, wherein the ultrasonic head is moved between the recordings by machine. The method of claim 6, wherein the ultrasonic head is moved between the recordings by machine. The method of claim 5, wherein the ultrasonic head a position sensor through which the respective picking position is detected. The method of claim 6, wherein the ultrasonic head a position sensor through which the respective picking position is detected. The method of claim 1, wherein after a movement the patient or an organ affecting the target area, which exceeds a certain level, a new admission the 3-D image data and / or a re-registration done. The method of claim 11, wherein the resumption with a resolution that is lower than the first one Resolution is, and at which the recorded before the intervention 3-D image data corrected based on the newly acquired 3-D image data become. The method of claim 11, wherein the resumption with the first resolution and at least a portion of the 3-D image data recorded prior to the intervention be replaced by the newly recorded 3-D image data. The method of claim 11, wherein the patient or Organ movements by position sensors mounted in or on the patient be recorded. The method of claim 14, wherein based on motion data acquired by the position sensors, the 3-D image data or part of it can be suitably deformed to pass through it the movements changed the extent and location of the target area adapt.